The present invention relates to a barking method, and a device for utilization of the method.
It is previously known to perform barking of a log while the log is made subject to a linear displacement movement through and past a barking apparatus. As examples of such barking methods can be mentioned barking using barking means such as a chain, wire or similar device, which is brought to take up frictional contact against the log to be barked, as for example as disclosed in Swedish Patent SE 122 987, SE 124 273, SE 130 000, SE 139 367 or SE 145 114, and with necessary contact force being obtained by means of one or a number of spring members. An alternative embodiment, including a triangular link system carrying a barking knife and with springs causing contact pressure, and including a motor driven drive means, is disclosed in CH 233 629, as a complete unit intended to perform a rotary movement along a tree, thereby performing a surrounding barking operation by means of the barking knife.
Previously known methods do not facilitate adjustment of the removal capacity during the barking operation, since the contact pressure of the barking member against a log is entirely related to the force applied by the springs used. An ideally suited barking method should allow for such a continuous adjustment of the removal capacity, which should be related to the type of log, but also the existing season of the year, since barking can be performed with less contact pressure at higher temperature (summer time) than at a lower temperature (winter time). The spring members are also less suited for location within a barking unit, since small bark fragments can be located between adjacent turns in the springs, and thus completely change a predetermined contact pressure for the spring loaded barking members.